should i use 191.168.0... as internal network addresses

our network is comprised of 3 vlans and 1 lan. the main default lan is 191.168.0.1 - 191.168.1.255
our vlans are 192.168.10.1, 192.168.20.1 and 192.168.30.1. we have been having dns issues. i can do a search on our network for server name i get not found. if i search using ip address it is found. i can go into our dns server and some address show up and some do not. a weird thing is that if we use the dhcp server to hand out ips, some of our cell phones will not be able to connect to the signal. it can see the signal but can get an ip address. when we put our dhcp on our watchguard firewall the cell phones dont have an issue. we have been told we shouldnt be using the 191.168.0... as internal ip address, could confuse with the outside world. any ideas?

thank you